Inhibitory control impairment in social disinhibition following severe traumatic brain injury: An experimental study...

Inhibitory control impairment is highly prevalent following traumatic brain injury (TBI). There have not been any empirical investigations into whether this could explain social disinhibition following severe TBI. Further, social context may be important in studying social disinhibition. Therefore, the objectives of this research study were to investigate the role of inhibitory control impairment in social disinhibition following severe TBI, using a social and a nonsocial task.

This was a between-group comparative study. Twenty-six adult participants with severe TBI and 27 sex, age, and education-matched controls participated. Social disinhibition was assessed using the Frontal Systems Behavior Scale and the Social Disinhibition Interview. Inhibitory control was assessed using a social and a nonsocial go/no-go task. Two-way mixed analyses of covariance were used to test study hypotheses.

Overall, participants were slower, F(1, 43) = 9.841, p = .003, η_p² = .245, and made more errors of commission on no-go trials, F(1, 44) = 11.560, p = .001, η_p² = .208, on the social go/no-go task. When categorized based on disinhibition level (high vs. low), the high disinhibition group made more errors on the social task, F(1, 41) = 4.095, p = .050, η_p² = .091, than the low disinhibition group, and more errors on the social, compared to nonsocial task, task-group interaction, F(1, 41) = 7.233, p = .010, η_p² = .150.

Social disinhibition appears to be associated with inhibitory control impairment, although this is only evident when a social task is used. No relationship between social disinhibition and response speed was found. (PsycInfo Database Record (c) 2023 APA, all rights reserved).